Simple Model for Scattering of Acoustic Signals from Rough Surfaces
Abstract
Models based on a simplified Kirchhoff approximation and locally reactive impedance are used to characterize the acoustic signal reflected by the ground from an elevated source in the far field and received by an array of microphones. The surface of the ground is modeled as mostly smooth, but with small variations in the surface height. The height of the ground is modeled using two 1-D GaussMarkov processes. The signal propagation is modeled using geometric optics in a homogeneous atmosphere with the angle of incidence equal to the angle of reflectance. The ground impedance is modeled as locally reactive. For relatively smooth surfaces, these models result in the addition of phase noise with a multivariate Gaussian distribution incorporated into the reflected signal. For rougher surfaces, the effect of the ground results in phase noise that is multiplicative with a multivariate Gaussian distribution. These results can be incorporated into acoustic simulation software and the design and evaluation of beam-forming algorithms.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 2021
- Accession Number
- AD1144525
Entities
People
- Geoffrey H. Goldman
Organizations
- United States Army Research Laboratory